.w {
    width: 80%;
    max-width: 1200px;
    margin:  0 auto;
}
.warpBox {
    min-height: 100vh;
    background-repeat: repeat-y;
    background-size: 100%;
    background-image: url(../images/img/about_bg.png);
    padding-bottom: 9.2857rem;
}
.content_1 {
    padding-top: 2.5rem;
    font-size: 16px;
    line-height: 30px;
    color: #212121;
}
.content_1 .txt {
    font-size: 20px;
}
.txt-1 {
    text-indent: 2em;
    font-size: 18px;
}
.content_2 .item {
    max-width: 600px;
    max-height: 400px;
    position: relative;
    width: 49%;
    overflow: hidden;
    margin: 10px 0;
}
.content_2 img {
    width: 100%;
    height: 100%;
    display: block;
}
.content_2 .item>div{
    position: absolute;
    bottom: 0;
    color: #fff;
    left: 0;
    right: 0;
    padding: 1.7857rem 0;
    font-size: 1.7143rem;
    background-color: rgba(48, 48, 49, 0.7);
}
@media (max-width:900px) {
    .content_2 .item,.content_3 .item {
        width: 100%;
        margin-bottom: 30px;
    }
    .content_2 img {
        max-height: none;
    }
}
